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31.
Ramesh C. Kamboj Dinesh Kumar Rita Arora Surinder Berar Geeta Sharma 《Journal of heterocyclic chemistry》2013,50(Z1):E200-E203
The photo‐irradiation of thienylchromenone resulted in the regioselective cyclization which is exclusively controlled by the nature of solvent used as reaction medium. Compared to nonpolar medium, polar solvent furnished a diverse array of novel angular tetracyclic photoproducts with gem‐dihydro functionality and exocyclic double bonds on the fused pyran ring, which is unprecedented to best of our knowledge. 相似文献
32.
Gurjaspreet Singh Satinderpal Singh Mangat Jandeep Singh Aanchal Arora Ramesh K. Sharma 《Tetrahedron letters》2014
The copper-catalyzed ‘click silylation’ has been exploited for the chemical modification of γ-azidopropyltriethoxysilane (AzPTES) with a wide range of terminal alkynes (1a–1v) in a one-pot operation. The novel 1,2,3-triazole-triethoxysilane derivatives (2a–2v) were synthesized by this procedure and comprehensively characterized by IR spectra, 1H and 13C NMR, and HRMS studies. 相似文献
33.
rac-BINAP-PdCl2 catalytic system catalyzed Heck reaction of 3-formylquinolin-2-yl chlorides with methyl acrylate in DMA is described to the synthesis of methyl 3-(3-formyl-quinolin-2-yl)-acrylates, in good to excellent yields. The reaction could be also extended with other activated alkenes to afford Heck products. Fused-benzene ring in heterocyclic and carbocyclic moieties was found to enhance the yields. 相似文献
34.
Gagan Chhabra Chandra K. Singh Deeba Amiri Neha Akula Nihal Ahmad 《Molecules (Basel, Switzerland)》2021,26(5)
Immunomodulation of the tumor microenvironment is emerging as an important area of research for the treatment of cancer patients. Several synthetic and natural agents are being investigated for their ability to enhance the immunogenic responses of immune cells present in the tumor microenvironment to impede tumor cell growth and dissemination. Among them, resveratrol, a stilbenoid found in red grapes and many other natural sources, has been studied extensively. Importantly, resveratrol has been shown to possess activity against various human diseases, including cancer. Mechanistically, resveratrol has been shown to regulate an array of signaling pathways and processes involving oxidative stress, inflammation, apoptosis, and several anticancer effects. Furthermore, recent research suggests that resveratrol can regulate various cellular signaling events including immune cell regulation, cytokines/chemokines secretion, and the expression of several other immune-related genes. In this review, we have summarized recent findings on resveratrol’s effects on immune regulatory cells and associated signaling in various cancer types. Numerous immunomodulatory effects of resveratrol suggest it may be useful in combination with other cancer therapies including immunotherapy for effective cancer management. 相似文献
35.
Sunanda Sharda Neha Sharma Pankaj Sharma Vineet Sharma 《Journal of Thermal Analysis and Calorimetry》2014,115(1):361-366
Differential thermal analysis (DTA) has been employed to investigate the effect of Ge addition on the glass transition behavior and crystallization kinetics of Sb10Se90?xGex (x = 0, 19, 21, 23, 25, 27) alloys. The three characteristic temperatures viz. glass transition (T g), crystallization (T c), and melting (T m) have been determined and found to vary with the heating rates and Ge content. Thermal stability and glass forming tendency have been evaluated in terms of ΔT (= T c ? T g) and reduced glass transition temperature. The activation energies for glass transition and crystallization have been used to analyze the nucleation and growth process. The activation energy analysis also determines the suitability of alloys to be used in switching applications. Results have been interpreted in terms of bond energies and structural transformations in the investigated alloys. 相似文献
36.
Harpreet Kaur Daljit Singh Arora Vishal Sharma 《Applied biochemistry and biotechnology》2014,173(8):1963-1976
A fungal culture (Penicillium sp., HT-28), isolated from soil has been evaluated for its bioactivity, which showed broad spectrum antimicrobial activity and was effective against methicillin-resistant Staphylococcus aureus (MRSA) also. Statistical optimization of the medium by response surface methodology (RSM) enhanced the antimicrobial activity up to 1.8-fold. Column chromatography was used to isolate the active compound (A), which was characterized to be 6-[1,2-dimethyl-6-(2-methyl-allyloxy)-hexyl]-3-(2-methoxy-phenyl)-chromen-4-one by various spectroscopic techniques such as infrared (IR), 1H and 13C nuclear magnetic resonance (NMR) spectra, and mass spectroscopy. Minimum inhibitory concentration (MIC) of the active compound (A) ranged from 0.5 to 15 μg/mL. Viable cell count studies of the active compound (A) showed S. aureus, Escherichia coli, Staphylococcus epidermidis, and Salmonella typhimurium 1 to be the most sensitive. The compound retained its bioactivity after treating it at 100 °C for 1 h. Furthermore, the compound (A) when tested for its biosafety was found neither to be cytotoxic nor mutagenic. The study demonstrated that an apparently novel compound isolated from Penicillium sp. (HT-28) seems to be a stable and potent antimicrobial. 相似文献
37.
Neha Batra Vinoth Rajendran Ishan Wadi Ankit Lathwal Roshan Kumar Dutta Prahlad C. Ghosh Rinkoo D. Gupta Mahendra Nath 《Journal of heterocyclic chemistry》2020,57(4):1625-1636
A series of benzenesulfonamide-appended [1,2,3]-triazole hybrids was synthesized by using [3 + 2] cycloaddition of primary, secondary, and tertiary sulfonamide azides with various phenoxymethylacetylenes under click reaction conditions. After structural characterization, the compounds were subjected to in-silico absorption, distribution, metabolism, excretion and toxicity (ADMET) screening to evaluate their drug-likeness and other pharmacokinetic parameters. Furthermore, their in vitro antiplasmodial potential was assessed against Plasmodium falciparum (3D7) strain, and some of the synthesized compounds displayed promising antimalarial potency. On cytotoxicity evaluation using MTT cell viability assay, the most active candidate N-(4,6-dimethylpyridin-2-yl)-4-(4-(4-nitrophenoxy)methyl)-1H-[1,2,3]-triazol-1-yl)benzenesulfonamide ( 14 ; IC50 6.2 μg/mL) demonstrated CC50 7.5 μg/mL against human hepatocarcinoma (HUH-7) cells. 相似文献
38.
Single crystals of potassium dihydrogen phosphate, KH2PO4 (KDP), grown by isothermal evaporation at room temperature have been characterized by their measurement of electrical conductivity and dielectric behaviour. Implications in respect of practical utility of KDP crystals in devices have been given. 相似文献
39.
Thin flakes of tin disulphide single crystals grown using direct vapour transport have been subjected to characterization to unfold their growth mechanism. Two types of spirals. viz. those having opposite orientation present on the same face and those present on the opposite finished faces are significantly discussed. 相似文献
40.
Qualitative and semiquantitative study of the Liesegang rings formed by the reaction of oxalic acid and cadmium chloride in the acidic range of pH in silica hydrogel is made. The behaviour of Jablczynski's space constant and Morce-Pierce's time constant at various temperatures, pH and concentration of outer electrolyte is studied. The possible mechanisms for the above observed behaviour are suggested. The deviations from Isemura's general obserations are interprerted by considering two particular aspects, viz., comparatively larger crystals constituting the rings and the irreversibility of inner and outer electrolytes. 相似文献